Potato resistance to quarantine diseases

Abstract

The causal agent of potato wart Synchytrium endobioticum (Schilb.) Perc. and golden potato cyst nematode (GPCN) Globodera rostochiensis (Wollenweber) Behrens are the quarantine species causing the most widespread and destructive diseases of potato in the Russian Federation and other countries. The pale potato cyst nematode Globodera pallida (Stone) Behrens is not found in Russia, although in the European Union it is found everywhere. This review provides information on the harmfulness of S. endobioticum and GPCN. To date, 43 pathotypes of S. endobioticum and 5 pathotypes of GPCN have been revealed in the world. In the Russian Federation, only the first (D1) pathotype of potato wart and pathotype Ro1 of GPCN have been found. Modern sets of differentials for S. endobioticum and GPCN and methods to determine the pathotype composition, including efforts to develop molecular markers (SSRs) to determine the race of S. endobioticum, are presented. The data on the resistance of commercial potato cultivars to these quarantine diseases and methods to determine resistance against them are reviewed. The modern data on the genetics of potato resistance to S. endobioticum, G. rostochiensis, and G. pallida, including mapping and cloning R-genes, are presented. The available published data on the molecular markers of R-genes for marker-assisted selection (MAS) and the evaluation of their effectiveness are presented. The use of multiplex systems allows the presence of several resistance genes to one or more pathogens to be analyzed at the same time. Mechanisms of potato’s quantitative resistance to S. endobioticum and GPCN and adaptation processes in pathogen populations resulting in overcoming the resistance of the host are discussed. The cultivation of varieties poorly susceptible to GPCN can stimulate the adaptive variability of the pathogen and induce virulent pathotypes for two or three pathogen generations.